Lifting-jack



' (No Ismal.)`

W. JOHNSON.

LIFTING JACK.

Patented Feb. 13, 1894.

WALTER J OHNSON, OF MIDDLETOWN, CONNECTICUT.

LIFTINGQJACK.

SPECIFICATION forming part of Letters Patent No. 514,755, dated February13, 1894.

Application tied october e, '1893.

To a/ZZ whom it may concern:

Be it known that I, WALTER JOHNSON, residing at Middletown, in thecounty of Middlesex and State of Connecticut, have invented certain newand useful Improvements in Lifting-Jacks, yof which the following is aspecification. v

My invention is an improvementin lifting jacks, and consists in thespecial construction whereby the jack may be locked at any height towhich it maybe adjusted all as will hereinafter be more fully describedand pointed out in the claims.

. In the drawings, Figure l is a side View of my lifting jack'.- Fig. 2is a detail side View partly in section showing the parts locked in fullview and unlocked in dotted lines, and Fig. 3 is a detail sectional viewon aboutline 3 3 of Fig. 1.

The jack comprisesa standard A, mounted on asuitable base B, and thelifting piece C which may be stepped as shown and provided with the pinD and the `series of holes to receive it; or may be otherwise adapted toengage under the vehicle axle. This lifting piece is connected with thestandard by the link E and the hand lever F pivoted both to the standardand lifting piece as shown. By the handle lever the lifting piece may beeas-v ily raised to any desired height. To lock it at such point Iprovide a detent which consists of a curved bar G sliding between twobinding or contact surfaces H I, in the standard and having anadjustable connection with the handle lever so that it may be settoslide between or bind such surfaces H and I as desired.

The binding surfaces are shown as arranged out of alignmentv with thepivot f of the hand lever, the lower surface I being nearer to thesliding or lifting piece thanv the upper surface H and these surfaces Hand I are preferably afforded by pins between which the detent barslides as shown.

In the construction shown, and, as preferred, the adjustable connectionbetween the curved bar and the handle lever is effected by means of aleverJ pivoted to the lever F and having itslong arm extended adjacentto said handle lever and its short arm linked to the curved bar asshown. This lever J is pref- Serial No. 487.340. (No model.)

erably a rod bent to form the long and short arms and also the portionswhich fulcrum in the arms f f of the handle lever.

In operation if the lever J be left free the handle lever F may bedepressed to elevate the lifting piece but cannot be raised because thedetent bar will bind between the surfaces H and I on its return movementand thus lock the detent bar against the return movement and so hold upthe lifting piece and the load it supports. To release-the detent it isonly necessary to lift the long arm of the lever up against the handlelever which by reason of the proximity of such parts may be easilyaccomplished. rlhis operation moves the detent out of binding contactwith the surfaces H and I and permits it to move freely in eitherdirection so that the lifting piece may be moved up or down as desired.

Having thus described my invention, what I claim, and desire to secureby Letters Pat- 1. A lifting jack provided with a lifting piece, orportion, means for raising the same, a detent bar and contact surfacesbetween which said bar plays andbinds, substantially as set forth.

2. A lifting jack comprising the standard having contact surfaces, thelifting piece, the handle lever for operating and binding in certainadjustments such lifting piece, the detent operating between saidcontact surfaces and an adjustable connection between said detent andthe handle lever substantially as set forth.

3. The combinationin alifting jack of the standard, the lifting piece,the handle lever, a'curved detent adjustably connected with said leverand binding or contact surfaces between Which suchy detent plays andbinds, substantially as and for the purposes set forth.

1I. The improved lifting jack herein described comprising the standardhaving upper and lower contact surfaces, the handle lever, and thedetent bar connected with saidI handle lever and arranged to playbetween said contact surfaces and to bind between said surfacessubstantially as set forth.

5. The combination in a lifting jack with the standard having contactsurfaces, the handle lever and the detent playing and binding betweensaid contact surfaces of a lever pivoted to the handle lever andconnected Wlth the detent; whereby to secure the detent adgustably tothe handle lever all substantially as set forth.

6. In a lifting jack the combination of the standard having the opposingContact surfaces, the handle lever, the detent bar playlng and engagingbetween the said surfaces, and the lever pivoted tothe handle lever andhaving its short arm connected with the detent bar and its long armextended adjacent to the handle lever substantially asset forth.

7. The improved lifting jack herein described, eonsisting of thestandard having stantially as and for the purposes set forth. 25

WALTER JOHNSON.

Witnesses:

P. I3. TURPIN, HARRY J. ROBINSON.

